Present day process of virtualization of network entities and attaching them to a Hypervisor is mostly concerned with layer-2 based entities and server-level hypervisor.
Virtualization of layer-3 entities is almost always done on proprietary basis, and the way the VNEs are attached to a network level, if any, Hypervisor uses proprietary interface.
These currently available/practiced methods and solutions create islands of virtualized layer-3 networks and services and defeat the entire motivation1 of using virtualization. For examples, some solutions focus solely on network operating system, some provide seamless access to network management aspects of virtualized entities (not necessarily always the VNEs), and others attempt to support distributed network elements (often virtualized); all use proprietary interface to often ‘undefined’ or proprietary network hypervisor. 1 The motivation is to share distributed virtualized resources seamlessly across different domains based on the demand from applications and services.
The current invention focuses on open and interoperable NHV based solution instead of operating on layer-2-based Hypervisor domain.
Note that layer-2-based Hypervisor typically covers broadcast domain over small geographical (room, campus, a small city, etc.) area, whereas the network layer covers a wide geographical area (like big city, state, country, and beyond), and hence is more attractive for automated load balancing and disaster recovery.